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Patent Oppositions

Sterne Kessler can help you avoid infringing competitors’ patents. Learn how we can represent you in opposition proceedings.

Oppositions or validity challenges can be filed against patents granted in Europe, Japan, Australia, New Zealand and elsewhere. Sterne Kessler works closely with clients to determine the best country in which to file an opposition and when it is well-advised to file an opposition.

Sterne Kessler challenges patents on behalf of clients by filing oppositions or cancellation requests in a court or patent office. By having a patent significantly amended or even declared invalid during an opposition/cancellation proceeding, we help clients avoid infringement damages.

As part of a global patent procurement and freedom-to-operate strategy, we analyze competitors' patents or applications, and then we work closely with clients to determine the best country in which to file an opposition.

Europe, Japan, Australia, New Zealand or elsewhere — the decision to file oppositions or validity challenges against patents requires in-depth knowledge of the interplay between U.S. and international patent law and global business strategies.

Foreign Oppositions — Considerations

  • Cost-effectiveness. The cost of an opposition proceeding in a foreign country is significantly less than U.S. or foreign litigation. Companies are using oppositions more and more as a cost-effective offensive tactic.
  • Effect on competitive positions in the United States. Companies often file the same patent application in many foreign countries. Some of our clients have no interest in foreign commercialization of a product, but filing an opposition in Australia, Europe or elsewhere may help to weaken the competitor's patent position in the United States.
  • Timing of filing. The timing of oppositions filing varies by jurisdiction — for example, in Europe, an opposition must be filed within nine months from the date of publication of the grant of the patent. In Japan, however, trials for invalidation may be filed at any time during the life of the patent.
  • Testing for U.S. enforcement strategy. Arguments in support of amendment and invalidity can be "road-tested" in a foreign jurisdiction before pursuing a similar, more costly strategy in the United States.
  • Influencing competitor’s U.S. enforcement strategy. The defeat of a patent in a foreign country will give a competitor something to consider before engaging in patent litigation in the United States.
  • Effect on U.S. patent prosecution outcomes. Opposition proceedings may be considered material to prosecution in the United States of a related application and would consequently have to be disclosed to the U.S. Patent Office.

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